OBJECTIVE To test whether the number or percentage of positive biopsy cores can be used to discriminate between patients with prostate cancer of a favourable and less favourable Gleason score (GS) /=3) were stratified into low- vs high-risk groups. Subsequently, we stratified patients according to the GS and the percentage of positive biopsy cores (/=50%). The pathological stage and the 5-year biochemical recurrence (BCR)-free survival rates were examined in univariable and multivariable models. RESULTS Based on the number of positive cores, the rate of extraprostatic disease was 11.7% and 23.3%, respectively, in the low-and high-risk GS